Add 'discard' request handling

[linux-2.6-omap-h63xx.git] / include / linux / bio.h

diff --git a/include/linux/bio.h b/include/linux/bio.h
index 17f1fbdb31bffff2d56942e188c8e6405cb61553..1fdfc5621c83ee4686800def5af4f8e731ce1206 100644 (file)
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -149,6 +149,8 @@ struct bio {
  * bit 2 -- barrier
  * bit 3 -- fail fast, don't want low level driver retries
  * bit 4 -- synchronous I/O hint: the block layer will unplug immediately
+ * bit 5 -- metadata request
+ * bit 6 -- discard sectors
  */
 #define BIO_RW         0       /* Must match RW in req flags (blkdev.h) */
 #define BIO_RW_AHEAD   1       /* Must match FAILFAST in req flags */
@@ -156,6 +158,7 @@ struct bio {
 #define BIO_RW_FAILFAST        3
 #define BIO_RW_SYNC    4
 #define BIO_RW_META    5
+#define BIO_RW_DISCARD 6
 
 /*
  * upper 16 bits of bi_rw define the io priority of this bio
@@ -186,13 +189,14 @@ struct bio {
 #define bio_rw_ahead(bio)      ((bio)->bi_rw & (1 << BIO_RW_AHEAD))
 #define bio_rw_meta(bio)       ((bio)->bi_rw & (1 << BIO_RW_META))
 #define bio_empty_barrier(bio) (bio_barrier(bio) && !bio_has_data(bio))
+#define bio_discard(bio)       ((bio)->bi_rw & (1 << BIO_RW_DISCARD))
 
 static inline unsigned int bio_cur_sectors(struct bio *bio)
 {
        if (bio->bi_vcnt)
                return bio_iovec(bio)->bv_len >> 9;
-
-       return 0;
+       else /* dataless requests such as discard */
+               return bio->bi_size >> 9;
 }
 
 static inline void *bio_data(struct bio *bio)